CVE-2026-111809: Apache Traffic Server · HTTP Request/Response Smuggling
Affects Apache Traffic ServerSource CVE Database V5
Not known to be exploited · CVSS 9.3 Critical.
Data as of 26 Oct 2026, 14:18 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 21 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Apache Software FoundationApache Traffic Server | Affected
| Fixed in– |
AI-suggested
Users should upgrade Apache Traffic Server to versions 9.2.16, 10.1.5, or 10.2.1, which contain official fixes for this vulnerability. Applying these updates will remediate the inconsistent HTTP request interpretation and prevent request smuggling attacks. No other mitigations are specified.
Description
Apache Traffic Server versions 8.0.0 through 8.1.11, 9.0.0 through 9.2.15, 10.0.0 through 10.1.4, and 10.2.0 are vulnerable to HTTP request smuggling via HEAD requests that include Content-Length or Transfer-Encoding headers. This vulnerability is identified as CWE-444, involving inconsistent interpretation of HTTP requests. The issue allows attackers to interfere with request processing, potentially leading to information disclosure and request manipulation. Upgrading to versions 9.2.16, 10.1.5, or 10.2.1 addresses this vulnerability.